This application relates to printing scratch-off documents. More specifically, the present disclosure relates to a scratch-off document and method of printing an embedded security code within the scratch-off layer of a document such as an instant lottery ticket, a gift card, or another document having a scratch-off layer.
Scratch-off type documents, such as instant lottery tickets, typically contain printed data on a substrate which is covered by a scratch-off material to hide the printed data. The scratch-off material may be removed by rubbing it with a hard object, such as a coin or fingernail, to reveal the underlying printed data. The scratch-off material, however, must sufficiently adhere to the substrate so that ordinary handling will not remove the scratch-off material.
Producing scratch-off documents involves complex printing applications which require high volume, low cost printing and other areas of variable data such as winning indicia, number marking and bar code generation. Adding to the complexity of manufacturing scratch-off tickets is the need to protect winning tickets from detection. Examples of detection include the ability to read the indicia that the ticket is a winning ticket prior to its purchase. For instance, infrared detection may serve to identify, or read, winning tickets. Another method of detecting a winning ticket includes scratching off the scratch-off material to find the winning ticket and then recoating the material onto the ticket. Unscrupulous individuals may then knowingly sell losing tickets. Such methods of detection are also possible for other value documentation readings having content to be protected, such as bank mailings containing PIN codes.